Valve for fluid operated rotary engines

ABSTRACT

A rotary control valve for a fluid operated motor the valve having a rotary valve rotor driven at motor speed and a rotationally adjustable valve sleeve in the valve rotor to vary the cut off of admission through the valve. The valves are so dimensioned that fluid pressure maintains contact between the valves at the area of their ports and the valve rotor is adjustable axially for long period admission. Provision is made for the control valve to operate a two stage motor and either series or parallel operation.

States Patent Lines 1 Jan. 9, 1973 VALVE FOR FLUID OPERATED 2,870,721 H1959 Orshansky, Jr ..9|/503 ROTARY ENGINES [76] mentor: Raydon Ayeirs Lines Rasp Primary Examiner-Robert M. Walker Avenue, Medmdie, Australia Attorneyl(mzer, Dorn & Zlckert [22] Filed: Jan. 27, 1971 Appl. No.: 110,097

Foreign Application Priority Data Jan. 29, 1970 Australia ..PA 0190/70 U.S. Cl ..9l/503 Int. Cl. ..F01b 3/00, FOlb 13/04 Field of Search ..4l7/62, 519; 415/151, 149, 415/155, 44, 45; 91/503 References Cited UNITED STATES PATENTS 8/1950 Greenhut ..9l/503 X [57] ABSTRACT A rotary control valve for a fluid operated motor the valve having a rotary valve rotor driven at motor speed and a rotationally adjustable valve sleeve in the valve rotor to vary the cut off of admission through the valve. The valves are so dimensioned that fluid pressure maintains contact between the valves at the area of their ports and the valve rotor is adjustable axially for long period admission. Provision is made for the control valve to operate a two stage motor and either series or parallel operation.

9 Claims, 12 Drawing Figures PATENTEDJAN ems 3.709.102

SHEET 3 OF 4 VALVE FOR FLUID OPERATED ROTARY ENGINES This invention relates to an improved valve for fluid operated rotary engines.

Fluid operated rotary engines have already been proposed in which a rotating valve with appropriate porting was used to control the flow of fluid to and from the rotors.

In engines of this type, particularly those operated by steam where an expansion factor has to be taken care of for efficient operation, it is necessary to change the duration of admission of the steam or the like during each cycle, so that full use can be made of the expansion factor.

In engines of this type it is also desirable to be able to get a very high starting torque and this generally envisages the use of high and low pressure steam sections which can be used appropriately for most effective operation, both at low speed and at high speed.

The general construction of the type of engine to which the invention is particularly adapted to which it need not necessarily be limited, is one in which each engine sector comprises a pair of rotors which have a generally cylindrical periphery with the two rotors in contact and housed in a chamber and each rotor being provided with a tooth or vane which moves around the chamber as the rotors rotate, the rotors being provided with recesses to allow the vanes to pass the contact point of the rotors and thus define the starting point of each cycle.

Preferably two such pairs of rotors are used, one being a high pressure section and the other a low pressure section, the high pressure section, of course, having rotors of narrower width than the high pressure section, so that the necessary expansion characteristics are observed.

The present invention is directed particularly to a valve for control of the operation of this type of rotary engine as applied to steam driven units, but the invention could apply also to other forms of expanding fluid drives such as hot gas engines.

According to my invention the valve mechanism is such that the main control which operates during the normal functioning of the engine, such as when a vehicle to which it is fitted is travelling at normal road speeds, but the valve can be changed to make it suita' ble to give high starting torque so that the necessary acceleration is available at periods where low rotor speeds would exist at which stage, of course, it would be desirable to develop a high torque to get a quick start after which the valve mechanism should change in function to give the best and most economical cruising and higher speed operation.

This is achieved according to this invention firstly by utilizing a valve assembly of the rotary type in which porting is such that by control of an adjustable valve sleeve, the duration of supply of the steam or similar medium to the rotors is controllable so that although the starting point of the admission for each cycle remains the same, the cut off point can be varied to allow different expansion ratios to exist.

The construction of this section is such that the admission can take place through about [80 of rotation of the valve, but beyond this it is necessary to resort to a different form of operation and another section of the A still further feature of the invention is the parallel ing of a high pressure and low pressure section rotor assembly during starting so that the sections are both supplied with high pressure steam or similar medium at the starting stage, so that a very high starting torque is available, but as the speed increases, through adjustment of thevalve mechanism, the high pressure section only receives the initial supply of steam or the like, and the exhaust from this is then fed to the low pressure section.

By then controlling the period of admission to the high pressure cylinder during this stage, it will be realized that a very effective and flexible form of control is available, which will allow the exact admission period to be selected in relation to the speed of the vehicle at the time.

While the actual construction of the invention can be quite considerably varied, a preferred embodiment will now be described, but it is to be clear that the invention need not necessarily be limited to this.

Referring now to the drawings:-

FIG. 1 is a part sectional view of the valve assembly,

FIGS. 2 and 3 are respectively a sectional view and end view of the high pressure valve rotor,

FIGS. 4 and 5 are respectively a side view and end view of the high pressure inner valve sleeve,

FIGS. 6 and 7 are respectively a sectional view and a plan view of the low pressure inner valve sleeve,

FIGS. 8, 9 and 10 are respectively a side view, plan view and end view of the low pressure valve rotor,

FIG. 11 is a sectional view of the high pressure exhaust valve, while FIG. 12 is a sectional view of the bypass valve assembly.

Referring firstly to FIG. 1 the casing of the motor has provided in it a housing 1, the housing having a high pressure inlet port 2 and a high pressure inlet port 3 to the high pressure chamber 4 of the rotary engine. The rotary engine which is this embodiment is described as a steam engine includes an intermediate chamber 5 into which the exhaust of the high pressure chamber 4 is exhausted to enable the high pressure exhaust to be admitted through port 6 and through the valve to be later described to be fed to the inlet port 7 of the low pressure chamber 8.

Referring to FIGS. 1, 2 and 3 there is disposed within the cylindrical bore housing 1 a high pressure valve rotor 9 provided with a port 10 coinciding with the inlet port 3 to the rotary engine. The high pressure valve rotor 9 is driven by a driving connection 60 from a drive shaft 11, the drive shaft being driven by a gear or tooth sprocket 12 which is splined to the shaft 11. The port 10 extends around the valve rotor 9 for approximately and as'the drive shaft is driven at a speed corresponding to the motor speed this port 10 in the valve rotor 9 controls the admission of steam to the inlet port 3.

Within the valve rotor 9 is an adjustable inner valve sleeve 13 (FIGS. 1, 4 and 5) which is again ported with a port 14 to correspond to the location of the inlet port 3 of the chamber 4. The valve sleeve 13 does not rotate with the valve rotor 9 but is adjustable rotationally to vary the cut off point of the flow of steam through the port 3 into the chamber 4. This rotational adjustment is provided by lugs which engage by pins 16, a ring 17 which is pinned by pins 18 to a sleeve 59 the pins 16 and 18 being spaced rotationally by 90. The sleeve 59 is adjusted either manually or automatically by a control system to thus change the rotational position of the inner valve sleeve 13 relative to the port 3 to thus vary the cut off of the steam being admitted.

To enable a larger period of admission to the high pressure rotor chamber 4 during starting the high pressure valve rotor (FIGS. 1, 2 and 3) is adjusted axially so that a series of ports 19 which extend for example 270 around the valve rotor 9 are aligned with the port 3 during rotation of the valve rotor 9, the valve sleeve 13 in this instance being adjusted for maximum cut off. Referring to FIG. 3 these ports 19 are shown as a series of closely spaced drilled holes extending around part of the circumference of the valve rotor 9.

As noted earlier the valve rotor 9 is attached to and driven by the shaft 11 and to move the valve rotor axially the shaft 11 is moved. This is accomplished by the action of steam pressure on the valves to be later described.

Hence it will be seen that the high pressure steam flows into inlet port 2 through port 8 into the interior of the inner valve sleeve 13 through port 14, port 10 in the rotor valve and into the high pressure rotor chamber, an isolating bearing being provided to prevent the flow of high pressure steam into the low pressure area of the control valve to be later described.

The exhaust from the high pressure chamber 4 is exhausted into the intermediate chamber 5 and through ports 6 (shown in broken lines) into the low pressure control valves. The steam flows past a sleeve keyed to shaft 11 and into the low pressure valves. Sleeve 20 drives by a pin connection the low pressure valve rotor 21 (FIGS. 1, 8, 9 and 10) which has port 22 corresponding to port 7 leading to the low pressure rotor chamber 8, the ports extending approximately 180 around the circumference of the valve rotor 21.

Similar to the high pressure valve arrangement the low pressure valve controls the cut off of the admission of steam to the low pressure rotor chamber. This is accomplished by a low pressure inner valve sleeve 23 having ports 24. The inner valve sleeve is adjusted rotationally and this is done by a shaft 25 to which is affixed a yoke 26 joined by pins 27 to the lugs 28 of the inner valve sleeve. The low pressure steam in the low pressure valve area acts against the isolating bearing between the low and high pressure valves, thus tending to move the high pressure valve to the left in FIG. 1, but this pressure is balanced as will later be described.

Hence it will be seen that there is provided control of the steam flow to the high pressure and low pressure stages.

However to facilitate starting when a larger starting torque is required further control valves are provided to admit the high pressure steam to both rotor chambers simultaneously so that the rotors are in efiect paralleled. This is achieved by a bypass valve 29 (FIGS. 1 and 12) and a high pressure chamber exhaust valve 30 (FIG. 11). These valves operate in syncronism so that when high pressure steam is applied by bypass valve 29 to passage 31 leading to the low pressure valves the exhaust valve 30 operates to divert the high pressure exhaust to either atmosphere or to a condenser.

In FIG. 1 the bore into which the simplingvalve 29 is to be inserted is shown, the valve itself being omitted from FIG. 1 for clarity. A passage 2a leads from the high pressure inlet port 2 to the valve 29, which valve when opened allows the high pressure steam to enter passage 31. The high pressure exhaust valve. is not shown in FIG. 1 and is located on the rotary engine. This valve is situated to divert the high pressure exhaust from the high pressure stage either directly to exhaust or to the passage 5.

Turning the FIG. 12 the bypass valve has a port 32 opening into the high pressure steam inlet duct 2a, the port 32 being adapted to be closed by a valve 33 which operates in a chamber 34 having an aperture 35 leading to the duct 31. The valve is operated by a piston 36 attached to the valve rod 36a so that when high pressure steam. is applied through the port 37 to the outer end of the piston the valve 33 moves to close port 32. When pressure is not applied to port 37 the pressure of steam through port 32 applied against valve face 35 moves the valve to the position shown. Also shown is a bleed port 38 to relieve any pressure that exists behind the piston 36 and which may leak past the valve stem.

FIG. 11 shows the high pressure chamber'exhaust valve 30 which controls the flow of exhaust steam to either the intermediate chamber or to exhaust to atmosphere or to a condenser. The exhaust of the high pressure rotor chamber flows throughport 39 into the valve chamber 40,- the port 41 leading to the intermediate chamber 5. A valve 42 operates in the chamber to either close port 41 or to close port 43 which leads to atmosphere or the condenser. To operate the valve 42 the valve stem 44 is provided with a piston 45 in a cylinder 47 to which is applied steam through port 48 to move the valve to close the port 41. Return movement of the valve 42 to close the port 43 is achieved by a spring. A bleed passage 46 between the piston chamber and the exhaust allows bleeding of any steam which may leak past piston 45.

Hence it will be seen that for starting the motor where high torque is required high pressure steam is applied to the low pressure valve area and the high pressure steam in this area is utilized to move the control shaft 11 axially as indicated hereinabove by the high pressure steam exerting a pressure on the end of the shaft 11 and isolating bearing which terminates at its driving connection to the low pressure valve rotor 21.

The other end of shaft 11 is provided with a collar 47 on which is mounted a bearing 48 which bearing bears against a flanged plunger 49 the plunger having a piston area 50 operating in a bore 51. A coil spring 52 bears against the flange of the plunger-49 and against the housing cap 53. A tapped connection 54 leads to the bore 51 while a further tapped connection 55 leads to the area of the spring 52. This tapped connection 55 is a bleed connection to bleed any excess steam which may exist in this area. A further bleed passage 56 leads through the flange to the bearing 48 and passages 57 and 58a lead to the area at the end of the flange.

Hence when connection 54 is open to atmosphere and high pressure steam is admitted to the low pressure valve area the steam exerts a pressure on the shaft at this area and moves the shaft axially (to the left as shown in FIG. 1) thus bringing the ports 19 of the high pressure rotor valve into operation. When it is desired upon the motor gaining sufficient speed control of the valve operates to apply high pressure steam to the connection 54 thus the shaft 11 is balanced hydraulically, and spring 52 moves the shaft 11 axially (to the right as shown in FIG. 1) to bring the port into operation.

This movement can be done or at the same as the change from parallel to series operation occurs it being realized that the appropriate high or low pressure steam be applied at connection 54 to maintain the hydraulic balance of the shaft. A connection 58 from the low pressure valve area could be utilized so that as pressure changes in the low pressure valve area this correspondingly is applied to connection 54 by a control valve which could exhaust connection 54 as required.

It will be realized that various bearings and seals are provided in the control valve it not being necessary to fully describe these as these are commonly used bearings and seals.

It has been found that to provide adequate sealing between the various parts of the valves that is between the valve rotor (9 or 21) and the housing 1 and between the inner valve sleeves (13 or 23) and the valve rotor (9 or 21) that it is practicable to provide these with a suitable small clearance therebetween. Also the connections between the shaft 11 and the valve rotor 9 and the valve rotor 21, and the connection between the adjustment means for the inner valve sleeve 13 and 23 are given a small amount of 3 freedom so that as steam flows from the interior of the inner valve sleeves 13 and 23 through the valves the steam pressure is effective in maintaining the valve rotors and sleeves in a direction towards the inlet ports of the rotor chamber so that effective sealing occurs between all ports. The figures of 180 and 270 previously mentioned are arbitrary selected only because these arcs could be varied in practice. It will be realized that the control valves could be incorporated in a suitable control system which is governed by operating conditions of the engine so that all the valve movements would take place automatically. It will also be noticed that the control valve rotors and sleeves are all balanced hydraulically so that excessive thrusts do not occur during the movements of these valves. in a preferred form of the invention the control valve is incorporated with a rotary steam engine in which lubrication of the valve and steam engine is effected by a soluble oil being incorporated with the steam this soluble oil then effectively lubricating all the bearings of the control valve.

lclaim:

l. A rotary control valve for a fluid operated motor, the valve including a housing, a hollow rotary valve rotor in the housing driven in syncronism with the fluid motor and an adjustable sleeve in the rotor whereby as fluid flows from the interior of the sleeve through ports in the sleeve and the rotor the duration of admission of fluid through the valve can be varied.

2. A rotary control valve for a fluid operated motor including a housing, a bore in the housing, a hollow rotary valve rotor freely rotatable in the bore and driven in syncronism with the fluid motor, and a rotationally adjustable sleeve in the rotor the relative diameters of the bore, the rotor and the sleeve being such that as fluid flows form the interior of the sleeve through ports in the sleeve and rotor to ports through the bore of the housing the steam pressure is effective in maintaining the sleeve in sealing relation with the rotor and the rotor in sealing engagement with the bore at the circumferential area of the ports in the bore.

3. A rotary control valve for a fluid operated motor, the valve including a ported rotary valve rotor cooperating with a ported valve bore, a rotationally adjustable valve sleeve in the rotary valve rotor to vary the admission through the rotary valve rotor and means to move the valve rotor axially to bring a further series of circumferential ports into operation so that an extended period of fluid admission is provided to the ports in the valve bore.

4. A rotary control valve where a two stage fluid operated motor the valve including a high pressure ported rotary valve rotor driven by a shaft and operating in a valve bore in the casing of the motor, the valve bore having ports leading to the high pressure chamber of the motor, a low pressure rotationally adjustable valve sleeve in the high pressure rotary valve rotor to vary the admission of steam from the interior of the high pressure valve sleeve through the high pressure valve rotor to the high pressure chamber, and a high pressure inlet to the valve bore for the admission of high pressure fluid to the interior of the valve sleeve, a low pressure ported rotary valve rotor driven by the drive shaft and operating in the valve bore and cooperating with ports in the valve bore leading to the low pressure chamber, and an adjustable low pressure valve sleeve in the low pressure rotor to vary the admission of low pressure fluid to the low pressure chamber, the low pressure fluid being fed to the interior of the low pressure valve sleeve from the exhaust of the high pressure chamber.

5. A rotary control valve as defined in claim 4 including valve means to divert high pressure fluid from the high pressure inlet to the interior of the low pressure valve sleeve, and further valve means to divert the exhaust from the high pressure chamber of the motor to exhaust to atmosphere or a condenser, the operation of the valve means and the further valve means being synchronized.

6. A rotary control valve as defined in claim 4 wherein the fluid is steam and the high pressure valve sleeve and the low pressure valve sleeve vary the cut off of admission of steam to their respective chambers of the steam operated motor.

7. A rotary control valve as defined in claim 4 including means to move the high pressure valve rotor axially to bring a further series of ports in the high pressure valve rotor into alignment with the ports leading to the high pressure chamber so that a longer period of admission is available.

8. A rotary control valve as defined in claim 4 wherein the drive shaft and the high pressure valve rotor are movable axially, one end of the drive shaft terminating in the low pressure valve area and being hydraulically balanced by fluid pressure in the low pressure valve area being applied to the other end of the drive shaft which drive shaft is biased into one axial position by spring means, means being provided to repressure fluid flow to the high pressure stage only or divert part of the high pressure fluid to the low pressure stage, and a high pressure exhaust valve to selectively divert the high pressure exhaust either, to the low pressure chamber or to exhaust to atmosphere.

* i I F 

1. A rotary control valve for a fluid operated motor, the valve including a housing, a hollow rotary valve rotor in the housing driven in syncronism with the fluid motor and an adjustable sleeve in the rotor whereby as fluid flows from the interior of the sleeve through ports in the sleeve and the rotor the duration of admission of fluid through the valve can be varied.
 2. A rotary control valve for a fluid operated motor including a housing, a bore in the housing, a hollow rotary valve rotor freely rotatable in the bore and driven in syncronism with the fluid motor, and a rotationally adjustable sleeve in the rotor the relative diameters of the bore, the rotor and the sleeve being such that as fluid flows form the interior of the sleeve through ports in the sleeve and rotor to ports through the bore of the housing the steam pressure is effective in maintaining the sleeve in sealing relation with the rotor and the rotor in sealing engagement with the bore at the circumferential area of the ports in the bore.
 3. A rotary control valve for a fluid operated motor, the valve including a ported rotary valve rotor cooperating with a ported valve bore, a rotationally adjustable valve sleeve in the rotary valve rotor to vary the admission through the rotary valve rotor and means to move the valve rotor axially to bring a further series of circumferential ports into operation so that an extended period of fluid admission is provided to the ports in the valve bore.
 4. A rotary control valve where a two stage fluid operated motor the valve including a high pressure ported rotary valve rotor driven by a shaft and operating in a valve bore in the casing of the motor, the valve bore having ports leading to the high pressure chamber of the motor, a low pressure rotationally adjustable valve sleeve in the high pressure rotary valve rotor to vary the admission of steam from the interior of the high pressure valve sleeve through the high pressure valve rotor to the high pressure chamber, and a high pressure inlet to the valve bore for the admission of high pressure fluid to the interior of the valve sleeve, a low pressure ported rotary valve rotor driven by the drive shaft and operating in the valve bore and cooperating with ports in the valve bore leading to the low pressure chamber, and an adjustable low pressure valve sleeve in the low pressure rotor to vary the admission of low pressure fluid to the low pressure chamber, the low pressure fluid being fed to the interior of the low pressure valve sleeve from the exhaust of the high pressure chamber.
 5. A rotary control valve as defined in claim 4 including valve means to divert high pressure fluid from the high pressure inlet to the interior of the low pressure valve sleeve, and further valve means to divert the exhaust from the high pressure chamber of the motor to exhaust to atmospheRe or a condenser, the operation of the valve means and the further valve means being synchronized.
 6. A rotary control valve as defined in claim 4 wherein the fluid is steam and the high pressure valve sleeve and the low pressure valve sleeve vary the cut off of admission of steam to their respective chambers of the steam operated motor.
 7. A rotary control valve as defined in claim 4 including means to move the high pressure valve rotor axially to bring a further series of ports in the high pressure valve rotor into alignment with the ports leading to the high pressure chamber so that a longer period of admission is available.
 8. A rotary control valve as defined in claim 4 wherein the drive shaft and the high pressure valve rotor are movable axially, one end of the drive shaft terminating in the low pressure valve area and being hydraulically balanced by fluid pressure in the low pressure valve area being applied to the other end of the drive shaft which drive shaft is biased into one axial position by spring means, means being provided to relieve the hydraulic balance though leaving the fluid pressure on the other end of the drive shaft and move the drive shaft axially into its other axial position against the bias of the spring means by the fluid pressure existing in the low pressure valve area.
 9. Control valve means for a two stage fluid operated motor including a sintling valve operable to allow high pressure fluid flow to the high pressure stage only or divert part of the high pressure fluid to the low pressure stage, and a high pressure exhaust valve to selectively divert the high pressure exhaust either to the low pressure chamber or to exhaust to atmosphere. 